A-Z Health Topics

Morton's Neuroma

(Interdigital Neuroma; Intermetatarsal Neuroma)

Definition

Morton's neuroma is painful thickening of the tissue around one of the nerves in the foot. It can affect any of the toes in the foot. However, it most often affects the nerves that run between the third and fourth, or second and third toes.

Causes

The thickening of the nerve caused by inflammation and the build up of fibrous tissue on the nerve's outer coating. This fibrous build-up is a reaction to the irritation resulting from nearby bones and ligaments rubbing against the nerves.

Irritation can be caused by:

Wearing shoes that are too tight

Wearing shoes that place the foot in an awkward position, such as with high heels

A foot that is mechanically unstable

Repetitive trauma to the foot such as from sports activities like tennis, basketball, and running

Trauma to the foot caused by an injury such as a sprain or fracture

It is unusual for more than one Morton's neuroma to occur on one foot at the same time. It is rare for Morton's neuroma to occur on both feet at the same time.

Risk Factors

Morton's neuroma is more common in women. Other factors that may increase your chance of Morton's neuroma include:

Activities that cause repetitive trauma to the foot such as sports-related activities

Symptoms

Morton's neuroma may cause:

Burning, pain, tingling, and numbness often shooting into the toes

Discomfort that is worse while walking

Feeling of a lump between the toes

Symptoms are usually temporarily relieved when:

Taking off the shoes

Flexing the toes

Rubbing the feet

Diagnosis

The doctor will ask about your symptoms and medical history. A physical exam will be done. Initial diagnosis of Morton's neuroma is based on your description of the type and location of pain and discomfort in the foot. The diagnosis will be confirmed by:

Physical exam of the foot, including:

Checking for mechanical abnormalities in the foot

Squeezing the side of the foot, which will usually cause pain when Morton's neuroma is present

Examination of your shoes to:

Check for excess wear in parts of the shoe

Check to see whether the shoes are too tight

Imaging tests evaluate the foot and surrounding structures. This may be done with:

Rehabilitation Measures to Reduce Nerve Irritation

Having ultrasound, electrical stimulation, whirlpool, and massage done on the foot

Injection of Medication

The foot may be injected with corticosteroids mixed with a local anesthetic in order to reduce pain. Relief may be only temporary however, if the mechanical irritation is not corrected. Injections with other types of medications such as alcohol, phenol, or vitamin B12 are sometimes used.

Surgery

Surgery to remove the neuroma may be recommended if more conservative treatment does not solve the problem. While surgery usually relieves or completely removes the symptoms, it often leaves a permanent numb feeling at the site of the neuroma.

Prevention

To help reduce your chance of Morton's neuroma:

Avoid wearing tight and/or high-heeled shoes.

Maintain or achieve ideal body weight.

If you play sports, wear roomy, properly fitting athletic footwear.

RESOURCES

American Podiatric Medical Association
http://www.apma.org

National Institute of Arthritis and Musculoskeletal and Skin Diseases
http://www.niams.nih.gov

CANADIAN RESOURCES

Canadian Orthopaedic Association
http://www.coa-aco.org

When it Hurts to Move—Canadian Orthopaedic Foundation
http://whenithurtstomove.org

This content is reviewed regularly and is updated when new and relevant evidence is made available. This information is neither intended nor implied to be a substitute for professional medical advice. Always seek the advice of your physician or other qualified health provider prior to starting any new treatment or with questions regarding a medical condition.